One in 110 American 8-year-olds has an autism spectrum disorder (ASD), a 57% jump in four years.

“This is a dramatic increase in the number of kids classified as autistic or documented on the spectrum of similar disorders,” explains study co-author Beverly Mulvihill, PhD. “It is not entirely clear what is causing the rise, but we know major collaborative efforts are needed to improve the understanding and lives of people and families impacted.”

The study also found that boys are 4.5 times more likely than girls to have ASD, a finding that confirms earlier studies, says co-author Martha Wingate, Dr.PH.

“It still is not clear why males more frequently are affected. One thing we know for sure is that more research is needed to quantify the effects of single or multiple factors such as diagnosis patterns, inclusion of milder cases and other components.”

MMWR – December 18, 2010.
www.cdc.gov/mmwr/